1. Field of the Invention
The present invention relates generally to skid steer loaders and their assembly.
2. Description of the Prior Art
Skid steer loaders are compact, highly maneuverable vehicles which are widely used in a variety of applications. Various techniques for manufacturing vehicles of this type are known and disclosed generally in the following United States patents, all of which are assigned to the same assignee as that of the present invention.
Heggen: U.S. Pat. No. 3,895,728 PA1 Heggen: U.S. Pat. No. 3,924,702 PA1 Bauer et al.: U.S. Pat. No. 4,055,262 PA1 Bauer et al.: U.S. Pat. No. 4,060,261 PA1 Henline et al.: U.S. Pat. No. 4,117,902 PA1 Bauer et al.: U.S. Pat. No. 4,131,225 PA1 Mather et al.: U.S. Pat. No. 4,535,868.
In general, known assembly methods begin with the fabrication and assembly of a subframe or transmission case, as disclosed for example in the Bauer et al. U.S. Pat. No. 4,131,225. The transmission case has a pair of axle housings, with axle shafts fit therein, welded to both sides. A hydraulic motor is mounted to each side of the transmission case between the axles. Gear and chain linkages within the transmission case couple each hydraulic motor to the axles on the side of the tranmission case to which it is mounted. Lateral flanges which function as floor plates are mounted to the front and rear axle housings.
Assembly continues by mounting a loader body or main frame such as that fabricated in accordance with the Bauer et al. U.S. Pat. No. 4,060,251 to gusset plates on the transmission case. The main frame includes a pair of longitudinally extending, laterally spaced side beams which are joined at the front by a wall member and at the rear by an upright fabrication which includes a bottom cross member. The upright fabrication includes a pair of uprights, one on each side thereof. A front cross member and a top cross member extend between the uprights at the front and top thereof. A rear cross plate extends between lower edges of the uprights. The uprights, front and top cross members, and rear cross plate partially define the engine enclosure.
The Mather U.S. Pat. No. 4,535,868 discloses a transverse engine mounting in which an engine and hydraulic pump mechanism are mounted to a bracket to form a subassembly. This subassembly is then installed in the engine compartment of the loader, on the rear cross plate. A radiator and oil cooler are mounted to the main frame in one of several known manners, and interconnected to the engine and hydraulics system. Connections between the hydraulic pump and hydraulic motors can also be made.
Following the above procedures, control mechanisms are mounted within the operator's compartment and interconnected to the hydraulic system. The operator's seat is added, and an overhead guard is mounted to the vehicle to enclose the operator's compartment. A boom assembly and bucket are mounted to the main frame. Assembly is then completed by adding wheels to the vehicle.
Skid-steer loaders fabricated and assembled in accordance with the above described method have proven to be rugged and reliable. Certain aspects of the assembly, however, are somewhat difficult. The loader is designed so as to be as compact as possible. As a result, space within the engine compartment is tight. It is therefore difficult to mount the radiator, oil cooler, engine and hydraulic pump within the vehicle. Hydraulic and mechanical interconnections between the engine and pump assembly, oil cooler, radiator, hydraulic motors, and other mechanical and hydraulic systems, as well as required adjustments, are difficult to make due to the limited amount of space in which to work. Difficult assembly procedures such as those discussed above increase the necessary assembly time of the loader.
However, the competitive marketplace places continuing demands for high quality loaders. It is evident that there is a continuing need for improved methods for assembling skid-steer loaders. Improvements which reduce assembly time and thereby increase efficiency are always desired. Structural integrity and durability of the vehicle must of course not be compromised.